In the world of renewable energy, solar thermal – heating water with the sun's power – is understandably the oldest and most mature field. That's because it's so simple: the sun has heated standing water for millennia and solar thermal systems simply add a technological aspect to improve efficiency, reliability and ease of use.
The fact that solar thermal has been around for a while has many benefits:
The bottom line with any renewable energy solution is, of course, whether it's worth the investment. Since solar thermal systems don't generate electricity and will never be a single solution for a net-zero or net-positive home, are they worth the money?
The simple answer is, as always, "it depends". Your particular location and circumstances will always determine whether any given option is suitable so you should look for a local expert with whom you can discuss options and possibilities.
When you're considering installing a solar thermal system, it's very important to consider all your options. Some of your choices will be governed by budget and climate; others are governed by what's practical for your home.
When you install a solar thermal system, you always need a collector (the bit that does the heating) and often need a tank (unless you're able to use a simple "batch system"). The tank is pretty simple but the collector format and setup is more complex.
Before you decide what kind of solar thermal system to install, you need to estimate your home's hot water use. There are two important parts to this equation: your actual water usage and your pattern of use. By changing the latter, you affect the former, so it's worth not only estimating but understanding how you and your family use water.
One of the first questions you need to ask yourself when considering solar thermal systems for hot water supply is whether you will need extra storage.
At their simplest, solar thermal systems simply heat water and send it to a standard, insulated hot-water tank, from where your home takes its supply. If the tank contains enough water for your needs, you may be able to opt for what's called a "batch system".
Solar thermal systems don't generate electricity: they just heat water. This means that they'll never give you a net-zero or net-positive effect if they're used on their own. On the other hand, they're more efficient than renewable electrical systems, have fewer demands and can take care of pretty much all your domestic hot water needs.
One of the more common misconceptions with homes using renewable energy is that they are totally independent, off-grid setups. In the vast majority of cases, this is not true: the home remains on the grid but offsets any external energy use with renewable sources so that the net cost or net use is zero (or better).
So you have decided that Solar is the right way to go. Whether you are looking at a Solar Thermal System or a Solar Photovoltaic Installation, you will have to spend quite a bit of cash. You see the benefits and the payback and you are ready to go, but how to pay for this system?
Heating Your Home with Solar Energy
